Fuel supply system

Abstract

A fuel supply system 1 includes an ecology device 6 that includes a first passage 11 and a second passage 12 , a cylinder 10 and a piston 14 provided between the first passage 11 and the second passage 12 , an urging portion 15 that urges the piston 14 , and a third passage 13 that branches off from the first passage 11 . A volume A 1 of the first space 31 of the cylinder 10 at the time of the engine operation of the gas turbine engine is defined as a first volume when operating B 1 . A total volume of fuel remaining in a fuel manifold 4 and a fuel nozzle 5 at the time of the engine stop of the gas turbine engine is defined as a required recovery volume D. The first volume when operating B 1 is greater than the required recovery volume D.

What is claimed is: 
     
         1 . A fuel supply system of a gas turbine engine, the fuel supply system comprising:
 a fuel tank;   a fuel manifold which supplies a fuel from the fuel tank to a fuel nozzle; and   an ecology device provided between the fuel tank and the fuel manifold to recover the fuel from the fuel manifold,   wherein the ecology device includes   a first passage connected to the fuel tank,   a second passage connected to the fuel manifold,   a cylinder which is provided between the first passage and the second passage and has a first port communicating with the first passage and a second port communicating with the second passage,   a piston which partitions an internal space of the cylinder into a first space communicating with the first passage and a second space communicating with the second passage, and slides inside the cylinder,   an urging portion which urges the piston from the second port side toward the first port side,   a third passage which branches off from the first passage and communicates with the second passage, and   a check valve which is provided in the third passage to block circulation from the second passage to the first passage,   a volume of the cylinder is equivalent to a total of a volume of the first space and a volume of the second space,   the volume of the first space of the cylinder at the time of engine operation of the gas turbine engine is defined as a first volume when operating, and   when a total volume in the fuel manifold and the fuel nozzle is set as a required recovery volume at the time of engine stop of the gas turbine engine,   the first volume when operating is greater than the required recovery volume.   
     
     
         2 . The fuel supply system according to  claim 1 , wherein the first volume when operating is determined by a balance between a pressure difference between the first space and the second space and a urging force of the urging portion at the time of the engine operation, and
 a magnitude of the urging force of the urging portion is set such that the first volume when operating is greater than the required recovery volume.   
     
     
         3 . The fuel supply system according to  claim 1 , further comprising:
 a stopper which is provided in the second space and restricts the movement of the piston to the second port side,   wherein the piston abuts on the stopper at the time of the engine operation,   the volume of the first space of the cylinder when the piston abuts on the stopper is defined as the first volume when operating, and   the stopper is provided at a position at which the first volume when operating becomes greater than the required recovery volume.   
     
     
         4 . The fuel supply system according to  claim 1 , wherein the first volume when operating has a magnitude equivalent to the required recovery volume. 
     
     
         5 . The fuel supply system according to  claim 1 , further comprising:
 an on-off valve provided in the first passage,   wherein the on-off valve is closed at the time of the engine stop for a short time.   
     
     
         6 . The fuel supply system according to  claim 1 , further comprising:
 a fourth passage which branches off from the first passage and is connected to the fuel tank; and   a selection switching valve which is able to switch the first passage and the fourth passage,   wherein at the time of the engine operation, the selection switching valve is controlled such that the fuel circulates through the first passage and is supplied to the ecology device, and   at the time of the engine stop, the selection switching valve is controlled such that the fuel recovered by the ecology device flows through the fourth passage and is returned to the fuel tank.   
     
     
         7 . The fuel supply system according to  claim 5 , further comprising:
 a fourth passage which branches off from the first passage and is connected to the fuel tank; and   a selection switching valve which is able to switch the first passage and the fourth passage,   wherein at the time of the engine operation, the selection switching valve is controlled such that the fuel flows through the first passage and is supplied to the ecology device,   at the time of the engine stop, the selection switching valve is controlled such that the fuel recovered by the ecology device flows through the fourth passage and is returned to the fuel tank, and   a three-way valve in which the on-off valve and the selection switching valve are integrated is provided at a connection portion between the first passage and the fourth passage.